This is the central hub and handle-coupling that joins a removable retractor blade to a reusable stainless-steel retractor handle (e.g. for Balfour, Finochietto, Army-Navy, Deaver and Weitlaner style retractors). The part is investment cast in AISI 420 stainless steel, a martensitic grade that takes a hard and wear-resistant surface after heat treatment, and tolerates repeated autoclave / chemiclave sterilisation cycles. Investment casting allows the multi-feature blade-clamp geometry (cam slot, spring recess, alignment pin, hand-pad relief) to be produced as a single piece with no weldments. Most of our retractor-hub customers replace a 5-axis machined-from-bar version with a near-net-shape casting to drop cycle time and unit cost in batches of 5,000–80,000 pieces.
Material Specifications
- Standard: AISI 420 (UNS S42000 / EN 1.4021 / ASTM A276 Type 420)
- Heat-treat condition: Hardened and tempered to ≈ 40–48 HRC per customer spec
- Composition reference: ASTM A276; EN 10204 3.1 chemistry certificate
- Bio-compatibility screening: ISO 10993-5 cytotoxicity report available on request
- Magnetic: Yes (martensitic; inform if MRI-conditional design is needed)
Dimensional Capability & Tolerance
- Weight range: 18 g – 200 g
- Min. wall thickness: 1.5 mm
- As-cast linear tolerance: ISO 8062 CT5 (≈ ±0.10 mm / 25 mm)
- CNC post-machining: ±0.04 mm on blade slot, handle bore, cam surface; coaxiality ≤ 0.05 mm TIR
- Wear surface hardness: depth-controlled case-hardening available on demand (to reduce surface galling)
- Inspection: 100% first-article CMM, FAIR per lot, retrofittable to PPAP-style controls for the OEM
Surface Finish Options
- CNC finished + passivated: Ra 0.8 – 1.6 µm (standard)
- Electropolishing: Ra ≤ 0.4 µm (for high-end reusable instruments)
- Mirror polishing: Ra ≤ 0.1 µm (for hand-held handle aesthetic zones)
- Black oxide / matte coating: optional for non-reflective surgical environments
Applications
- Balfour / Finochietto / Weitlaner retractor blade-to-handle couplings
- Army-Navy, Deaver, Kelly handheld retractor hub bodies
- Self-retaining retractor frames
- Veterinary surgical retractors
Why Choose Ningbo Ruican for This Part
- 17+ years of martensitic stainless-steel investment casting, in-house vacuum heat treatment and tempering
- Single-piece design vs. multi-weldment assemblies (no weld failure points in autoclave cycles)
- Tight grain structure and uniform hardness thanks to investment casting — better fatigue behaviour than forged-and-machined equivalents in service
- Customer-specific surface treatments (electropolish, mirror polish) available in-line with our CNC finishing cell
Certifications & Regulatory Positioning
- IATF 16949 (valid)
- EN 10204 3.1 chemistry and mechanical certificates — supplied per lot
- FAIR / ISIR per lot, raw-material lot traceability
- Project-level ISO 13485 documentation packages supplied on request; Ningbo Ruican is not an ISO 13485 contract manufacturer
